RAF Rivet Joint

[Chugalug2]

Squirrel 41, I'll leave JTO to address the points you make, but I'd just like to address the broader business of UK Military Airworthiness provision if I might.
Unbeknownst to me, and most of my fellow aviators at the time, a whole army of dedicated people were employed to ensure that the aircraft that I flew were airworthy (Chipmunk, Jet Provost, Hastings and Hercules in my case). Most of them were engineers, both CS and military, who ensured that these aircraft were constructed and operated iaw the UK Military Airworthiness Regulations.
The principle hurdle was the award of the Release to Service into the RAF or other UK Services. For this to happen the Controller Aircraft had to assure himself of the airworthiness of the aircraft (both in terms of construction and of operating, the latter being determined by Boscombe Down). Then and only then could the aircraft be offered for RTS which was the responsibility of ACAS, Both men had to agree and sign as such before the Scruggs Mk1 could go into Squadron service.
All that worked well, indeed worked better year by year as the system was honed by experience, until something went wrong. The something in my case was the tragic crash of a Hastings at Abingdon 6 July 1965, killing all 41 onboard. The cause was found to be the failure of the elevator outrigger bolts, thus removing all elevator control. Every RAF Hastings (not sure how many, say 60 odd?) was grounded until a repair requiring 1000s of man-hours to carry out (other problems at the tail empennage had been found as well). I was at Sydney at the time and spent the next two months, after the rest of the crew other than two groundcrew had returned to Changi, carrying out a weekly STI of starting up, taxying, shutting down the a/c. Even when I returned to Changi, as the rectification team had turned up at Kingsford-Smith, it was weeks before the Squadron was back to normal.
So that is what happened in the past. It contrasts sharply with what happened in the early 90's when the Chinook HC2 was granted an illegal RTS (CA had granted switch on only clearance, ie for ground instructional use only, the a/c was still being tested by Boscombe Down who grounded their aircraft as being "positively dangerous", and yet the a/c was already in Squadron service!). 29 people died at Mull, the BoI did not "discover" that the aircraft was grossly unairworthy (the positively dangerous bit was the FADEC coding, as well as UFCMs being experienced in 1,2,or all 3 axis!), the pilots were "found" to be Grossly Negligent, and the RAF still does not accept that they weren't. Yet this was a period that Haddon-Cave described as a Golden Period of Airworthiness!
The cover up of that scandal, that emanated from the even greater one that preceded it, of the deliberate dismantling of the airworthiness system that I described above, by sacking the majority of the engineers, CS or uniformed, who would not obey illegal orders to suborn the Regulations but sign them off as complied with anyway, continues to this day. Many of those who compromised themselves may still be in post today.
That is why the MAA cannot assure airworthiness, because it no longer knows how to. Every fleet is affected, not just the RJ, and the default solution of rewriting the Regs, grounding fleets or refusing RTS's to those that do not comply with them is a nonsense. There is now no RAF fleet that can be deemed airworthy IMHO, because the necessary system of continuous audit, both before and after entry into service, has not been maintained. Those that knew what they were doing are no longer there to do it.
What happens re the RJ, I have no idea. What must happen to the MAA and the MAAIB is to be made independent of the MOD and of each other, and then learn (via the CAA and AAIB) how to do their jobs again.